Why do we need OPC?
Why Do We Need OPC?
A pressing need in both factory automation and process manufacturing is making production and business systems work together. How many times has this been a barrier because of incompatibilities and proprietary communication interfaces between different suppliers' automation hardware and software? OPC gives production and business applications across the manufacturing enterprise access to real-time plant-floor information in a consistent manner, making multi-vendor interoperability and "plug and play" connectivity a reality.
Business Benefits of OPC
OPC promises what, up to now, has been virtually unachievable -- to provide multi-vendor plug-and-play components that manufacturing customers and system integrators can easily integrate into enterprise-wide automation and business systems. OPC removes barriers between traditionally proprietary factory floor devices, systems and other manufacturing software. OPC also delivers additional business benefits in the form of increased flexibility, and reduced system integration, development and installation costs of factory automation and process control systems. OPC is here and can help users solve real manufacturing problems today.
Current Status of the OPC Foundation and OPC Products
The OPC Foundation membership has grown to more than 275 companies worldwide. OPC is gaining worldwide acceptance that is strongly reflected in the makeup of the member companies. With strong participation in North America, Europe and Asia Pacific, OPC has the critical mass to achieve manufacturing customers' goals for ease-of-use, interoperability, and openness worldwide. The growing list of OPC compatible products is available under the Products section of the Foundation's web site, http://www.opcfoundation.org. Many National Instruments products have OPC support built-in, including LabVIEW with an OPC client and the Datalogging and Supervisory Control Module, FieldPoint and FOUNDATION Fieldbus interfaces with OPC servers. These OPC products are making it easy to exchange information between disparate automation devices, control systems and production applications running across the manufacturing enterprise.
Links to National Instruments Products for OPC
The Technology Behind OPC
OPC, based on the Component Object Model (COM) is part of The Microsoft .NET Framework®. OPC uses the Microsoft .NET Framework to provide plug-and-play connectivity and interoperability between disparate automation devices, systems, and software both on the factory floor and across the manufacturing enterprise. In short, Microsoft's COM specification provides the necessary software infrastructure that defines how applications share data under Microsoft operating systems like Windows NT. The OPC specifications define a set of standard COM objects, methods, and properties that specifically address requirements for real-time factory automation and process control applications. OPC servers provide a standard interface to the OPC COM objects, allowing OPC client applications to exchange data and control commands in a generic way. OPC client applications can communicate with one or more OPC servers from different suppliers. OPC client applications access data the same way whether the data is coming from an OPC server connected to a PLC, industrial networks like Foundation Fieldbus, Profibus or DeviceNet, a SCADA system, a Laboratory Information Management Systems (LIMS), or a production management system.
Where is OPC headed?
OPC is designed to be extensible. Since inception in 1996, the OPC Foundation has established various technical committees for extending the scope and function of OPC specifications to address a broader range of manufacturing connectivity and interoperability issues. OPC Foundation specifications now include OPC Data Access 3.0, OPC Alarms & Events, OPC Historical Data Access, OPC Batch, and OPC Security, plus two new specifications, OPC Data eXchange (DX) and OPC XML-DA.
OPC DX provides application interoperability between disparate fieldbuses. OPC DX standard provides interoperability between controllers connected to Ethernet networks using different protocols such as Ethernet/IP, PROFINet and Foundation Fieldbus High Speed Ethernet.
The OPC XML-DA specification leverages Internet technology such as extensible markup language (XML), HTTP and SOAP to provide a vertical communication link between the plant floor and manufacturing enterprise applications. OPC XML-DA provides several additional benefits including 1) the ability to publish plant floor data across the manufacturing enterprise using the Internet, 2) the capability to use XML, HTTP, SOAP and Internet technology to develop OPC XML-DA clients and servers on non-Microsoft platforms, and 3) the capability to publish plant floor data in formats that are easily used by enterprise applications such as manufacturing planning, scheduling, quality and asset management.
OPC will continue to grow as the open industry standard for manufacturing because the OPC Foundation members, like National Instruments, share a common vision -- to create a worldwide, industry standard for connectivity and interoperability across the manufacturing enterprise.